The spatiotemporal expression of cell surface molecules is under precise control during normal tissue morphogenesis. In many tumors, abnormal expression of cell surface molecules may recapitulate developmental expression patterns and correlate with the malignant properties of the tumor. We therefore propose to determine the expression of a number of developmentally regulated neural cell adhesion molecules and other cell surface molecules in a variety of primary brain tumors. These results will be correlated with the histology, grade, and clinical course of adult and pediatric tumors. Our goals are to: i) establish whether tumors of specific types and grades express characteristic patterns of certain cell surface molecules, ii) correlate transformative changes in certain tumors over time with changes in specific cell surface molecules, iii) determine whether the ability of tumor cells to metastasize in particular patterns correlates with the prevalence of certain adhesion molecules and iv) identify novel tumor specific markers that will be of therapeutic and diagnostic value. To this end we will compare the expression of several cell adhesion molecules, substrate adhesion molecules, proteoglycans, glycosylphosphatidylinositol-anchored proteins, glycolipids, and carbohydrate epitopes on pediatric and adult tumor specimens by a combination of immunoperoxidase staining, immunoblotting, and thin layer chromatography. The results will be correlated with tumor grade and type for various types of pediatric and adult tumors.